Search Publications
The metal-rich halo tail extended in |z|: a characterization with Gaia DR2 and APOGEE
Beers, Timothy C.; Chiappini, Cristina; Recio-Blanco, Alejandra +12 more
We report an analysis of the metal-rich tail ([Fe/H] > -0.75) of stars located at distances from the Galactic plane up to |z| ∼ 10 kpc, observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). We examine the chemistry, kinematics, and dynamics of this metal-rich sample using chemical abundances and radial velocities prov…
Activity and rotation of the X-ray emitting Kepler stars
Belfiore, A.; Marelli, M.; Poretti, E. +6 more
The relation between magnetic activity and rotation in late-type stars provides fundamental information on stellar dynamos and angular momentum evolution. Rotation-activity studies found in the literature suffer from inhomogeneity in the measurement of activity indexes and rotation periods. We overcome this limitation with a study of the X-ray emi…
The Disappearing Solar Filament of 2013 September 29 and Its Large Associated Proton Event: Implications for Particle Acceleration at the Sun
Kahler, S. W.; Shimojo, M.; Cliver, E. W. +1 more
We present observations of a notable example of a disappearing solar filament (DSF) on 2013 September 29 that was associated with a large solar proton event (SPE) and discuss this event in the context of four recent studies that compare flare and SPE size parameters. The DSF-associated flare was characterized by weak radio and soft X-ray emissions…
High-resolution Spectroscopic Analysis of a Large Sample of Li-rich Giants Found By LAMOST
Shi, Jianrong; Zhao, Gang; Blanco-Cuaresma, S. +6 more
The discovery of Li-rich giants has introduced a new challenge for standard stellar evolution models. To resolve this issue, the number of this type of object has been rapidly increased through the development of worldwide surveys. Taking advantage of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope survey, 44 new Li-rich giants are r…
Modelling accretion disc emission with generalized temperature profile and its effect on AGN spectral energy distribution
Jin, Chichuan; Yuan, Weimin; Liu, He-Yang +3 more
The broad-band spectral energy distribution (SED) of active galactic nuclei (AGNs) is investigated for a well-selected sample composed of 23 Seyfert 1 galaxies observed simultaneously in the optical/ultraviolet (UV) and X-ray bands with the Neil Gehrels Swift Observatory. The optical to UV continuum spectra are modelled, for the first time, with e…
Dense cores and star formation in the giant molecular cloud Vela C★★★
Hill, T.; Weiss, A.; Csengeri, T. +12 more
Context. The Vela Molecular Ridge is one of the nearest (700 pc) giant molecular cloud (GMC) complexes hosting intermediate-mass (up to early B, late O stars) star formation, and is located in the outer Galaxy, inside the Galactic plane. Vela C is one of the GMCs making up the Vela Molecular Ridge, and exhibits both sub-regions of robust and sub-r…
Can intrinsic alignments of elongated low-mass galaxies be used to map the cosmic web at high redshift?
Ferguson, Henry C.; Giavalisco, Mauro; Koekemoer, Anton M. +13 more
Hubble Space Telescope observations show that low-mass (M_*=10^9-10^{10} M_{⊙ }) galaxies at high redshift (z = 1.0-2.5) tend to be elongated (prolate) rather than disky (oblate) or spheroidal. This is explained in zoom-in cosmological hydrodynamical simulations by the fact that these galaxies are forming in cosmic web filaments where accretion ha…
The distance, rotation, and physical parameters of ζ Pup
Howarth, Ian D.; van Leeuwen, Floor
We scrutinize the Hipparcos parallax for the bright O supergiant ζ Pup and confirm that the implied distance of 332 ± 11 pc appears to be reliable. We then review the implications for the star's physical parameters and the consequences for the interpretation of Pphot, the 1.78-d photometric period. The inferred mass, radius, and luminos…
The Cassini VIMS archive of Titan: From browse products to global infrared color maps
Le Mouélic, S.; Cornet, T.; Rodriguez, S. +11 more
We have analyzed the complete Visual and Infrared Mapping Spectrometer (VIMS) data archive of Titan. Our objective is to build global surface cartographic products, by combining all the data gathered during the 127 targeted flybys of Titan into synthetic global maps interpolated on a grid at 32 pixels per degree (∼1.4 km/pixel at the equator), in …
Lyman-α emission in the Martian proton aurora: Line profile and role of horizontal induced magnetic field
Ritter, B.; Hubert, B.; Shematovich, V. I. +2 more
Enhancements of the dayside Lyman-α emission by as much as ∼50% have been observed between 120 and 130 km in the lower Martian thermosphere from the Mars Express and MAVEN satellites, usually following solar events such as coronal mass ejections and corotating interaction regions. They have been assumed to be optical signatures of proton aurora re…